/*
 * linux/lib/cmdline.c
 * Helper functions generally used for parsing kernel command line
 * and module options.
 *
 * Code and copyrights come from init/main.c and arch/i386/kernel/setup.c.
 *
 * This source code is licensed under the GNU General Public License,
 * Version 2.  See the file COPYING for more details.
 *
 * GNU Indent formatting options for this file: -kr -i8 -npsl -pcs
 *
 */
#include <seminix/string.h>
#include <seminix/kernel.h>
#include <seminix/ctype.h>

/*
 *	If a hyphen was found in get_option, this will handle the
 *	range of numbers, M-N.  This will expand the range and insert
 *	the values[M, M+1, ..., N] into the ints array in get_options.
 */

static int get_range(char **str, int *pint, int n)
{
    int x, inc_counter, upper_range;

    (*str)++;
    upper_range = simple_strtol((*str), NULL, 0);
    inc_counter = upper_range - *pint;
    for (x = *pint; n && x < upper_range; x++, n--)
        *pint++ = x;
    return inc_counter;
}

/**
 *	get_option - Parse integer from an option string
 *	@str: option string
 *	@pint: (output) integer value parsed from @str
 *
 *	Read an int from an option string; if available accept a subsequent
 *	comma as well.
 *
 *	Return values:
 *	0 - no int in string
 *	1 - int found, no subsequent comma
 *	2 - int found including a subsequent comma
 *	3 - hyphen found to denote a range
 */

int get_option(char **str, int *pint)
{
    char *cur = *str;

    if (!cur || !(*cur))
        return 0;
    *pint = simple_strtol(cur, str, 0);
    if (cur == *str)
        return 0;
    if (**str == ',') {
        (*str)++;
        return 2;
    }
    if (**str == '-')
        return 3;

    return 1;
}

/**
 *	get_options - Parse a string into a list of integers
 *	@str: String to be parsed
 *	@nints: size of integer array
 *	@ints: integer array
 *
 *	This function parses a string containing a comma-separated
 *	list of integers, a hyphen-separated range of _positive_ integers,
 *	or a combination of both.  The parse halts when the array is
 *	full, or when no more numbers can be retrieved from the
 *	string.
 *
 *	Return value is the character in the string which caused
 *	the parse to end (typically a null terminator, if @str is
 *	completely parseable).
 */

char *get_options(const char *str, int nints, int *ints)
{
    int res, i = 1;

    while (i < nints) {
        res = get_option((char **)&str, ints + i);
        if (res == 0)
            break;
        if (res == 3) {
            int range_nums;
            range_nums = get_range((char **)&str, ints + i, nints - i);
            if (range_nums < 0)
                break;
            /*
             * Decrement the result by one to leave out the
             * last number in the range.  The next iteration
             * will handle the upper number in the range
             */
            i += (range_nums - 1);
        }
        i++;
        if (res == 1)
            break;
    }
    ints[0] = i - 1;
    return (char *)str;
}

__diag_push()
__diag_ignore_all("-Wimplicit-fallthrough", "");

/**
 *	memparse - parse a string with mem suffixes into a number
 *	@ptr: Where parse begins
 *	@retptr: (output) Optional pointer to next char after parse completes
 *
 *	Parses a string into a number.  The number stored at @ptr is
 *	potentially suffixed with K, M, G, T, P, E.
 */

unsigned long long memparse(const char *ptr, char **retptr)
{
    char *endptr;	/* local pointer to end of parsed string */

    unsigned long long ret = simple_strtoull(ptr, &endptr, 0);

    switch (*endptr) {
    case 'E':
    case 'e':
        ret <<= 10;
    case 'P':
    case 'p':
        ret <<= 10;
    case 'T':
    case 't':
        ret <<= 10;
    case 'G':
    case 'g':
        ret <<= 10;
    case 'M':
    case 'm':
        ret <<= 10;
    case 'K':
    case 'k':
        ret <<= 10;
        endptr++;
    default:
        break;
    }

    if (retptr)
        *retptr = endptr;

    return ret;
}

__diag_pop();

/**
 *	parse_option_str - Parse a string and check an option is set or not
 *	@str: String to be parsed
 *	@option: option name
 *
 *	This function parses a string containing a comma-separated list of
 *	strings like a=b,c.
 *
 *	Return true if there's such option in the string, or return false.
 */
bool parse_option_str(const char *str, const char *option)
{
    while (*str) {
        if (!strncmp(str, option, strlen(option))) {
            str += strlen(option);
            if (!*str || *str == ',')
                return true;
        }

        while (*str && *str != ',')
            str++;

        if (*str == ',')
            str++;
    }

    return false;
}

/*
 * Parse a string to get a param value pair.
 * You can use " around spaces, but can't escape ".
 * Hyphens and underscores equivalent in parameter names.
 */
char *next_arg(char *args, char **param, char **val)
{
    unsigned int i, equals = 0;
    int in_quote = 0, quoted = 0;
    char *next;

    if (*args == '"') {
        args++;
        in_quote = 1;
        quoted = 1;
    }

    for (i = 0; args[i]; i++) {
        if (isspace(args[i]) && !in_quote)
            break;
        if (equals == 0) {
            if (args[i] == '=')
                equals = i;
        }
        if (args[i] == '"')
            in_quote = !in_quote;
    }

    *param = args;
    if (!equals)
        *val = NULL;
    else {
        args[equals] = '\0';
        *val = args + equals + 1;

        /* Don't include quotes in value. */
        if (**val == '"') {
            (*val)++;
            if (args[i-1] == '"')
                args[i-1] = '\0';
        }
    }
    if (quoted && args[i-1] == '"')
        args[i-1] = '\0';

    if (args[i]) {
        args[i] = '\0';
        next = args + i + 1;
    } else
        next = args + i;

    /* Chew up trailing spaces. */
    return skip_spaces(next);
}
